Bone marrow NK cell expression of degranulation markers in patients with NDMM and control subjects. (A) Bone marrow CD3^–CD56⁺CD16⁺ NK cells triple-positive for granzyme, perforin, and CD107a in NDMM and control subjects in the resting and stimulated state. (B) Correlation between survival and CD3^–CD56⁺CD16⁺ NK cell granzyme or perforin expression in NDMM.